Idiom meaning, usage examples, facts

1. John pushed his way in to the party and confronted Laura. He began to rant and rave and say things everyone knew he would later regret. He said a mouthful.
2. Everybody managed to keep the surprise party a secret until the last minute, when Jennifer’s younger sister gave it away. She said a mouthful before she remembered that the party was supposed to be a secret.

Compare to: go off half-cocked. The expression is usually used to describe when someone says a lot, not so much in terms of the number of words as in the significance of the words. 79